RESUMEN
BACKGROUND: Bullying leads to adverse mental health outcomes and it has also been linked to nonsuicidal self-injury (NSSI) in community adolescents. It is not clear whether different roles of bullying (bully, victim, bully-victim) are associated with NSSI, furthermore the same associations in cyberbullying are even less investigated. METHODS: The aim of the current study was to test whether students involved in school or online bullying differed from their not involved peers and from each other in psychological symptoms (externalizing and internalizing problems) and in NSSI severity (number of episodes, number of methods). Furthermore, mediation models were tested to explore the possible role of externalizing and internalizing problems in the association of school and online bullying roles with NSSI. In our study, 1011 high school students (66.07% girls; n = 668), aged between 14 and 20 years (Mage = 16.81; SD = 1.41) participated. RESULTS: Lifetime prevalence of at least one episode of NSSI was 41.05% (n = 415). Students involved in bullying used more methods of NSSI than not involved adolescents. In general, victim status was associated mostly with internalizing symptoms, while bully role was more strongly associated with externalizing problems. Bully-victims status was associated with both types of psychological problems, but this group did not show a significantly elevated NSSI severity compared to other bullying roles. Externalizing and internalizing problems mediated the relationship between bullying roles and NSSI with different paths at different roles, especially in case of current NSSI that happened in the previous month. CONCLUSIONS: Results highlight that students involved in bullying are more vulnerable to NSSI and to psychological symptoms compared to their peers who are not involved in bullying. It is suggested that bullying roles, especially bully-victim status, need to be identified in school and online settings and thus special attention should be addressed to them to reduce psychological symptoms and NSSI, for example by enhancing adaptive coping skills.